COVID-19: Omicron infections contagious for at least 6 days

Patients infected with the Omicron variant of SARS-CoV-2 remain contagious for just as long as patients infected with earlier variants, according to a small study.

Researchers took blood samples from 56 newly-diagnosed patients, including 37 with Delta infections and 19 with Omicron infections. All were mildly ill, such as with flu-like symptoms, but none were hospitalized. Regardless of which variant or whether or not they had been vaccinated or boosted, study participants “shed live virus for, on average, about 6 days after symptoms (began), and… about one in four people shed live virus for over 8 days,” said Dr. Amy Barczak of the Massachusetts General Hospital in Boston, who coauthored a report posted on medRxiv ahead of peer review.

“Although it is unknown exactly how much live virus is needed to spread the disease to others, we take these data to suggest that people with mild COVID-19 infection may be contagious on average for 6 days, and sometimes longer,” Barczak said. “Decisions about isolation and masking should take such information into account, regardless of variant or prior vaccination status.”

Heart defects boost risks for hospitalized COVID-19 patients

People born with heart defects who become sick enough from COVID-19 to be hospitalized are at higher risk for becoming critically ill or dying, researchers said.

The findings were drawn from a study that compared 421 patients with a heart defect who were hospitalized for COVID-19 with 235,638 similar hospitalized COVID-19 patients born with normal hearts. After researchers accounted for patients’ other risk factors, those with congenital heart defects were 40% more likely to be admitted to an intensive care unit, 80% more likely to need mechanical ventilation, and two times more to die while hospitalized, compared to patients in the control group, according to the report published on Monday in the journal Circulation.

Hospitalized patients with a congenital heart defect and another health condition faced even higher risks for poor outcomes, the researchers found.

“People with heart defects should be encouraged to receive the COVID-19 vaccines and boosters and to continue to practice additional preventive measures for COVID-19, such as mask-wearing and physical distancing,” study leader Karrie Downing of the U.S. Centers for Disease Control and Prevention said in a statement.